This application is based upon and claims the benefit of priority of Japanese Patent Application No. 2001-89791 filed on Mar. 27, 2001, the content of which is incorporated herein by reference.
1. Field of the Invention
The present invention relates to a fuel supply device in which a fuel injector (injector) connected to a fuel delivery pipe supplies fuel to cylinders of an internal combustion engine (engine).
2. Description of Related Art
As shown in FIG. 6, in a conventional fuel supply device in which injectors 110 supply fuel to cylinders of an engine, each fuel inlet 111 of the injectors 110 are inserted into each delivery port 101 of a fuel delivery pipe 100 and each fuel outlet of the injectors 110 (nozzle side) is to be inserted into the engine (not shown). Each of a clearance between an inner wall of the delivery port 101 and an outer wall of the fuel inlet 111 and a clearance between an inner wall of the engine and an outer wall of the outlet of the injector 110 is sealed by a resilient seal member such as an o-ring 112. Each of the injectors 110 is sandwiched between and fixed to the engine and the fuel delivery pipe 100.
In this supply system, a clip 120 (a joint member) prevents each of the injectors 110 from slipping out of the fuel delivery pipe 100. Accordingly, in a state in which the injectors 110 are assembled to the delivery pipe 100, the fuel supply device can be easily moved to another place for mounting the respective outlets of the injectors 110 on the engine.
However, the conventional clip 120 has a drawback that, once the clip 120 is fitted both in the injector 110 and the fuel delivery pipe 100, the injector 110 can not move axially, that is, in a direction in which the injector 110 is inserted into or drawn out of the fuel delivery pipe 100, since the clip 120 is engaged not only with projections 102 formed in an outer wall of the fuel delivery port 101 but also with a groove 113 formed in the injector 110. Therefore, even if the o-ring 112 for sealing is in an abnormal state due to twisting or getting out of position after the injector 110 has been inserted into and assembled to the fuel delivery pipe 100, the abnormal state can not be easily corrected by further inserting the injector 110 into or drawing out of the fuel delivery pipe 100.
An object of the invention is to provide a fuel supply device having a slip-out preventing member that allows an injector to be further inserted into or to be drawn out of a fuel delivery pipe, even after the slip-out preventing member is fitted in the fuel delivery pipe and the injector.
To achieve the above object, the fuel supply device has a fuel delivery pipe having a plurality of fuel delivery ports, electrically operated fuel injectors each having a fuel inlet whose outer wall of the fuel inlet is inserted into and frictionally engaged with each inner wall of the fuel delivery ports, a fuel outlet whose outer wall is to be inserted into an internal combustion engine and a protruding portion between the fuel inlet and outlet, and slip-out preventing members each engaged with each outer wall of the fuel delivery ports and holding each of the fuel injectors axially movably at a given distance.
With the fuel supply device, each of the slip-out preventing members has a stopper which comes in contact with the protruding portion of the injector, when each of the fuel injectors is moved in a direction of drawing out of each of the fuel delivery ports, so that the injectors never slip out of the delivery pipe.
In a state in which the injectors are assembled to the delivery pipe, the fuel supply device can be easily moved to another place, for example, for mounting the respective fuel outlets of the injectors on the engine.
It is preferable to dispose a sealing member such as O-ring for sealing a clearance between the outer wall of the fuel inlet and the inner wall of the fuel delivery port.
In this case, even if the sealing member is in an abnormal state due to twisting or getting out of position when the injector is inserted into and assembled to the fuel delivery pipe, the abnormal state can be easily corrected by further inserting the injector into or drawing out of the fuel delivery pipe.
Preferably, the protruding portion is a connecter integrally provided in the fuel injector for supplying an electric power thereto. Accordingly, the fuel supply device is compact.
Further, it is preferable that each of the slip-out preventing members has a pair of opposed arms between which a part of the fuel injector between the protruding portion and the fuel outlet is sandwiched so as to allow the fuel injector to move axially, and two pawls each provided in each end of the arms so as to constitute the stopper.
As an alternative, each of the slip-out preventing members may have a ring plate which surrounds an entire outer circumference of a part of the fuel injector between the protruding portion and the outlet so as to allow the fuel injector to move axially and which constitutes the stopper.